Variable condenser



Nov. 10, 1925. 1,560,761

L. COHEN VARIABLE CONDENSER Filed June 5, 1922 5 fm1. I

LOMI COHE/l/ Patented Nov.` l0, 1925.

UNITED STATES LOUIS COHEN, OF WASHINGTON, DISTRICT 0F COLMBIA.

VARIABLE CONDENSER.

Application med :une 5, 1922. semi No. 565,920.

To all whom t may concern.'

Be it knownthat LoUIs COHEN, a citizen of the United States, residing at1656 Euclid Street NW., Washington, D. C., have invented certain new anduseful Improvements in Variable Condensers, of which the following is aspecification.

This invention relates to variable condensers in general and moreparticularly to an improved means for adjusting the movable plates ofvariable condensers.

The object of my invention is to provide a variable condenser of smalldimensions and capable of a wide range of capacity variation. Y

f Another object is to provide a variable condenser which is rugged inconstruction, reliable in operation, and which will eliminate anypossibility of short circuits which danger is frequently 'encountered inthe usual type of variable condenser.

Other objects and advantages will appear in the description in thespecification.

The above objects and advantages have been accomplished by the deviceshown in the accompanying drawings.

Figupe 1 is a side view of the variable condenser;

Figure 2 is a sectional view of the condenser;

Figure 3 is a plan view of the condenser.

Referring more particularly to the drawings. the device consists of aplurality of fixed plates 1 and movable plates 2. A thin sheet ofinsulating material 3, preferably composed of mica, is arranged on eachmovable plate 2; The fixed plates 1 are mounted stationary on supportingmembers 4 of the casing 5. These supports 4 may all be metal butpreferably one only, the remainder beingy composed of insulatingmaterial, the metal support connecting all the fixed plates electricallyin parallel.

A `centrally disposed partially screwthreaded shaft 6 is arranged in thecasing 5, the lower end of the shaft 6 being free t0 turn in the bearingmember 26. a bushing 9 forming the bearing for the upper part of theshaft.

An interiorly screw-threaded sleeve 7 is mounted on the shaft 6 in sucha manner that as the shaft is rotated the sleeve is raised or loweredthereby, depending upon the direction of rotation 0f the shaft. Aplurality of plates 2 are fixedly mounted on vtween the fixed plates.

the sleeve 7 and are arranged alternately with relation to thestationary plates 1.

In order to limit the travel of the sleeve 7 on the shaft 6 a stop lugor disc vor the like 19 is fixed on the shaft 6, limiting such travel byabutting against the upper extremity of the sleeve A suitable gear 10 isfixed on the shaft 6 and meshes with a corresponding gear 13. Gear 13 isfixed on a spindle 22 which is rotatably mounted in the casing top plate24 and carries a gear 12 which meshes with a corresponding gear 11. Gear11 is fixed to the sleeve 27 which carries an indicating dial 8. Asuitable lmob 18 is arranged 0n the shaft 6 to enable the easy operationthereof.

A lead 15 connects the sleeve 7 to the binding post 16, therebyconnecting all the movable plates 2 to said binding post 16. Anotherbinding post 17 is directly connected to the metal support 4 of thefixed plates. The -operation of the device in varying the capacity ofthe condenser is clearlyunderstood. By turning the :knob 18 androtating'the shaft 6 a vertical movement of the sleeve 7 is effected,thus moving the lates 2 which are rigidly'attached to the s eeve 7. Onthe upward motion ofthe sleeve 7, the plates 2 may be brought into closeproximity to the Icorresponding fixed plates, the only separation beingthe thin insulation material 3 which is preferably of mica sheet, andwhich can be made as thin as desirable within practical limits. Makingthese mica sheets very thin the plates are brought together ver closeand-the capacity for each pair of p ates may be considerable. Theseveral pairs of plates are connected electricall in multiple, therebygiving aconsidera le capacity. On the downward motion` of the sleeve 7 astop 19 is provided so that the movable plates 2 are carried downwardonly to about half the distance be- The distances between adjacent fixedplates may be determined so as to make the capacity, when the plates areseparated by half the distance between the fixed plates, extremelysmall. It is quite obvious that with this arrangement there is nopossibility of short circuiting because of the mica insulation be-ytween each pair of plates. The gearing arrangementsindicated by 10, 11,12 and 13 are for the purpose of controlling the travel of the dial 8and they are so proportionedv ywhich can begraduated in degrees or in'any other desired manner which would give an indication of the magnitudeof .the capacity for any position of the movable plates With respecttothe fixed plates. Asmall gear 10 is mounted on the shaft 6 whichengages a largegear 13, this gear 13 is mounted on a shaft '22 and onthe same shaft aI smaller gear 12 is mounted which engages the largergear 11, and'this large gear 11 is mounted on a sleeve 9 to which isattachedv the dial 8. By this arrangement the rotary motion of `theshaft 6 is transferred to the dial 8 and a reduced motion is obtained,the diameters of the gears are so proportioned that if necessary evenseveral revolutions of the shaft 6 will effect only half a revolution ofIthe dial 8, so that for the complete travel of the movable plates 2,the dial 8 travels only one half a revolution.

Figure 3 shows a top view of. the condenser in which 23 is an indicatedelement attached permanently to the case of the condenser, 8 is the dialgraduated in degrees, and 18 is the'handle for turning the shaftG. Inoperation'the handle 18 is turned until the desired capacity within therange of the condenser is obtained and is indicated by the point on thedial facing the zero point marked 23. The dial is originally so set thata minimum capacity is indicated by the zero point on the dial.

Claimsy 1. A variable condenser comprising a plu-- rality of fixedplates, and a plurality of movable plates, sai movable plates beingmounted 'on an interiorly screw-threaded sleeve and engaging a threadedshaft, the rotation of said shaft being adapted to reciprocatevertically said movable` plates, and thereby effect various desireddegrees of separation between said'movable andr fixed plates of saidvariable condenser, said stationary plates being provided at theirperipheries "withspacing and supporting members.

2. In a variable condenser, an outer cylindrical casing, a plurality ofstationary and movable plates mounted therein, a centrally disposedinteriorly screw-threaded sleeve, al

screw-threaded shaft mounted therein and adapted toA verticallyreciprocate said sleeve sai movable plates bein fixedly mounted on saidsleeve and mvab e with said sleeve, v said stationary plates beingprovided at their y:

Yperipheries vwith spacing and supporting members and said movableplates being adapted to be adjusted with relation to said stationaryplates for the purpose of valving the capacity of said condenser, saidshaft having a stop mounted thereon limiting the movement of saidsleeve, a gear mounted on said shaft adapted to mesh with a second gearmountedon a spindle adapted to rotate 'a third gear, said third gear inturn rotating a fourth gear mounted on a dial-carryin sleeve for thepurpose of rotating said in icating dial.

3. In a -variable condenser, an outer casing provided with peripherallyarranged spacingl and supporting members, a plurality of insulatedstationary plates mounted thereon, a cent-rally disposed screw-threadedshaft, an interiorly screw-threaded sleeve mounted thereon and adaptedto bevertically actuated by said shaft, said sleeve being adapted tocarry a plurality of movable plates, the movement of said sleeve varyingthe distance between said stationary and said movable plates and therebyvarying the capacity of the condenser..

4. In a variable condenser a plurality of stationary plates provided attheir peripheries with spacing and supporting members, a plurality ofmovable plates vertically alternatively arranged, relative therewith,rotary operating means for reciprocating said movable plates and therebyvarying then' respective distances from the adjacent stationary plates,reduction transmission meansy connected to said operating means forimarting a less frequent rotation to a capaclty indicating dial.

5. In a- 'variable condenser a plurality of stationary plates providedat thelr peripheries with spacing and supporting members, aplurality ofmovable plates vertically al-` .means consisting of an interiorilyscrewv threadedsleeve adapted to carry said movable plates, and apartially screw-threaded rotary shaft adapted to reciprocate saidsleeve. y .y

In testimony whereof I aiix my signature.

LOUIS COHEN.

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